The present invention relates generally to packaging of optical fibers. More particularly, an embodiment related to a method and system for packaging of an optical fiber coil in a compact form that provides efficient heat sinking, but with minimal stress on the optical fiber. The present invention is not limited to this particular application, but has a wider field of use.
High power fiber lasers, such as high power pulsed fiber lasers, typically employ a fiber design referred to as Large Mode Area (LMA) fiber. These fibers are inherently multi-mode, and thus generally produce multi-mode outputs from fiber lasers and/or fiber amplifiers. High power fibers may be doped fibers, for example, doped with Ytterbium at 6×1026 ions/m3. Coiling the fibers is generally used in many fiber system in order to package the fiber in a convenient, small size. The coiling of fibers has been a challenge for many applications, as coiling may perturb modal properties of the fibers, resulting in undesirable modes being favored over a more preferred fundamental mode. In particular, if the fiber in the coil is heated as a result of the high power optical signal propagating in the fiber, thermal stress may be induced due to the differential thermal expansions between the fiber and the material in contact with the fiber, such as a metallic mandrel. The induced stress may cause variation in the achieved modes, which is undesirable.
Thus, there is a need in the art for methods and systems for packaging of fiber optics for high power applications.